Abstract: Urban metro hub construction faces a large number of deep excavations in downtown districts which exist many risks. This paper proposes a risk controlling method called “five steps in risk controlling” to eliminate the sources of risks and control the risk events. This method emphasizes that excavation is a systematic project which risks come from every phase, such as investigation phase, design phase, and construction phase. As the final executive of risk controlling, construction side should participate the risk management of the whole course of the excavation project. The five steps in risk controlling mainly include rechecking of the investigation data, negotiation of the design scheme, construction process control, analyzing and feedback of the monitoring data, and the emergency response of the risk events. This method will be helpful for controlling the risks of deep excavation in large metro hub constructing.  

Key words: rail transit, metro hub, super deep excavation, risk controlling, five steps in risk controlling